Reference

Reference.swift

public enum ReferencePolicy {
  case Strong, Weak
}

// Allows for a mix of strong and weak references inside Arrays and Dictionaries.
public class Reference <T: AnyObject> {

  public var object: T! {
    get { return _strong ?? _weak }
    set {
      if object === newValue { return }
      if policy == .Strong { _strong = newValue }
      else { _weak = newValue }
    }
  }

  public var policy: ReferencePolicy {
    didSet {
      if policy != oldValue { swap(&_weak, &_strong) }
    }
  }

  public var onDeinit: (Void -> Void)?

  public init (_ object: T! = nil, _ policy: ReferencePolicy = .Strong) {
    self.policy = policy
    self.object = object
  }



  
  private var _strong: T!
  
  private weak var _weak: T!

  deinit { onDeinit?() }
}